/*
 * Copyright 2002-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.lightcommons.resource;

import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.UnsupportedCharsetException;

/**
 * Simple interface for objects that are sources for an {@link InputStream}.
 * 
 * <p>
 * This is the base interface for Spring's more extensive {@link Resource}
 * interface.
 * 
 * <p>
 * For single-use streams, {@link InputStreamResource} can be used for any given
 * <code>InputStream</code>. Spring's {@link ByteArrayResource} or any
 * file-based <code>Resource</code> implementation can be used as a concrete
 * instance, allowing one to read the underlying content stream multiple times.
 * This makes this interface useful as an abstract content source for mail
 * attachments, for example.
 * 
 * @author Juergen Hoeller
 * @since 20.01.2004
 * @see java.io.InputStream
 * @see Resource
 * @see InputStreamResource
 * @see ByteArrayResource
 */
public interface InputStreamSource {

	/**
	 * Return an {@link InputStream}.
	 * <p>
	 * It is expected that each call creates a <i>fresh</i> stream.
	 * <p>
	 * This requirement is particularly important when you consider an API such
	 * as JavaMail, which needs to be able to read the stream multiple times
	 * when creating mail attachments. For such a use case, it is <i>required</i>
	 * that each <code>getInputStream()</code> call returns a fresh stream.
	 * 
	 * @throws IOException
	 *             if the stream could not be opened
	 */
	InputStream getInputStream() throws IOException;
	
	byte[] getByteArray() throws IOException ;

	char[] getCharArray(String encoding) throws IOException,UnsupportedCharsetException;

	String getText(String encoding) throws IOException,UnsupportedCharsetException;


}
